The main principle of stereoscopic display technology is to allow a viewer's left and right eyes to receive different images respectively, and the images received by the left and right eyes are analyzed and combined in brain, so that the viewer can have the senses of levels and depth of a displayed picture, and thus perceives a stereoscopic impression. Therefore, in order to make a display panel have a stereoscopic image display effect, it is necessary to provide a pair of images, one of which is only for left eye and the other is only for right eye, for same one picture, so as to achieve a stereoscopic display effect.
Currently, a approach commonly used for achieving stereoscopic display is to provide a liquid crystal lens in front of a display panel. The liquid crystal lens, by controlling the arrangement of liquid crystal molecules, causes a liquid crystal layer to have gradient refractive indices, so that the liquid crystal layer has a lens effect. For controlling the arrangement of liquid crystal molecules, a gradient electric field is needed.
As illustrated in FIG. 1, it is a schematic structural diagram of a liquid crystal lens in the prior art; the liquid crystal lens comprises: a first substrate 10 and a second substrate 20 which are provided opposite to each other, and a liquid crystal layer 30 filled between the first substrate 10 and the second substrate 20. On the surface of the first substrate 10 facing the second substrate 20, there is provided a common electrode 11, and on the surface of the second substrate 20 facing the first substrate 10, there are provided a plurality of strip-like electrodes 21 arranged at an equal interval. The liquid crystal lens further comprises a driver circuit (not shown), which is electrically-connected with the plurality of strip-like electrodes respectively. When the liquid crystal lens is in an energized state, each strip-like electrode 21 with cooperation of the common electrode 11 forms an electric field therebetween. By utilizing birefringence characteristic of liquid crystal molecules, as well as the light-focusing/diverging characteristic of liquid crystal molecules along with changes of electric-field intensity, and by using the driver circuit to apply different drive voltages to individual strip-like electrodes 21, i.e., by applying a different drive voltage to each strip-like electrode 21, electric fields of different intensities are formed by the strip-like electrodes 21 with cooperation of the common electrode 11 respectively, so that the liquid crystal molecules lying in different regions are subjected to different degrees of deflection, thereby enabling the liquid crystal layer to achieve a lens-like effect. By combining the liquid crystal lens with a display panel, a viewer is allowed to view left-eye images with only left eye and right-eye images with only right eye, so that the viewer can perceives a stereoscopic display feeling.
However, the liquid crystal lens described above needs a driver circuit to apply different drive voltages to different strip-like electrodes 21, so as to form gradient electric fields required for forming the liquid crystal lens, but as for such gradient electric fields obtained in this way, the drive mode is relatively complex, which is disadvantageous for promotion and development of the liquid crystal lens. Therefore, how to improve the drive mode of a liquid crystal lens nowadays has become an urgent problem to be solved.